Published German Patent Application No. 32 02 614 is representative of prior art relating to automatic control systems with error correction that form the background for the present invention. This patent discloses a device for regulating fuel injection when starting a self-igniting internal combustion engine. The regulating device has a PI-controller (proportional/integral controller) with an upstream counter. The PI-controller is connected to a sensor that detects the crankshaft position of the internal combustion engine.
The PI-controller receives a setpoint value derived from a characteristics field. The characteristics field is derived from operating parameters of the internal combustion engine. A second characteristics field, called a control characteristics field, also is provided. The output value of the second characteristics field is added to the output value of the PI-controller. If any error is detected, the output value of the PI-controller is disabled. An error condition exists, for example, when the sensor, the counter, or other components of the regulating device does not operate properly.